-x a air control device



. B. M. GUTHRIE 2,349,719 "AIR CONTROL DEVICE Fi'led Jan. 10, 1941 I May 23, 1944.

Earhart 7% Gd/if/ZB INVEMOR.

@Z Z ATroRNEY..

Patented May 23, 1944 UNITED STATES enre-NT OFFICE Bernard M. Guthrie, Kokomoylnd 'assignorto P g Kingston ProductsCorporation;'Kokomo, Ind,

a corporation of Indiana? Application January 10, 1941, seria1 No. 373,896 solaims, (01. 137- 152) This invention relates generally to air control means, and more particularly to an automatic air control device for use in conjunction with domestic stoker apparatus. l H

One particular object of the invention ,isto provide a durable air control device which isparticularly efiicient in operation whereby to obtain uniformand substantially complete combustion of the fuel to be consumed. p l

Another object is to provide "an air control device consisting of very few parts which can be economically manufactured and assembled on a production basis. l I

Other objects and advantages of the invention will be apparent after considering the description hereinafter set forth in conjunction with the drawing annexed hereto.

Referring to the'drawing: Figure lillustrates an application of the control device embodying the invention to the air supply apparatus of a conventional domestic heating plant, certain parts of which are; shown in section; Figure 2 is an end view in elevation of a part of the control device shown in Figure 3, certain partsof which are shown in section for the. purposes of illustrating certain details of, construction; l r,

Figure 3 is a side view in elevation of'the'control device, with certain parts in section;

Figure 4 is a partial view of the damper and bracket unit used in conjunction with the control device;

Figure 5 is a section takensubstantially, on line 5- -5 ofFigure 3;

Figure 6 is a section taken substantially on line 66 of Figure 2 showing certain details of construction; and t l H ,1 v,

Figure 7 is a partial 'VlBW, partly in section of the stop for limiting movement of the damper, including related structure, I r l The. air control device is particularly designed and constructed to prevent an excessive volume of air under pressure from passing into the retort: or fire pctwhen the fuel is not in the properv condition or state to receive such volume, particularly at a time when the fuel hasbecomequite porous by burning during the inactivity of the blower and stoker. The admission of a vast volume of air under pressure from the blower at such a timehas a tendency to disrupt the fuel bed and cause the scatteringof fly ash, and when new fuel is added the fire is temporarily smothered. In other words, the device is so constructed and arranged that the proper volume of air is admitted at the proper time whereby to obtain satisfactory combustion of the 'fuel.

It is therefore manifest that some form of automatic means is desirable for controlling the volume ofair admitted to the retort in accordance with the rate of fuel delivery whereby to obtain efi'icient results.

Considering how the structure illustrated in the drawing, particularly Figure 1, numeral I, generally. designates a stoker and 2 a heating unit, The stoker is provided with a hopper 3 and a blower 4, and the heating unit with a retort or fire pot 5 including an airchamber 6 adjacent the retort. A conveyor 1, preferably of the screw type, is disposed in a conduit 8 for conducting a predetermined: amount of fuel from the hopper through the conduit into the retort at a predeterminedrate, and a conduit 9 providesa passage throughwhich the air from the blower is directed under pressurefinto the air chamber 6 and out throughthe tlly res l0 into the retort 5 whereby to supply air to the fuel conveyed to the retort.

The above described structure may be of the conventional type, and the air control device generally designated II constituting the present inventionis adapted to be disposed at some desirable point Within the air conduit or duct 9 for automatically controlling or regulating the volume of air admitted to the fuel, and includes, among other things, a tubular housing l2 which carries a damper l3, and an element I4, preferably in the form of a dashpot, whereby to retard movement of the damper [3 within the housing The air control device II is designed and constructed so that it can be easily and .quickly installed, and this is preferably accomplished by inserting the ends I5 of the housing into the sectionsofthe conduit 9, the abutments l6 adjacent the ends providing stops engageable with the ends ofsaid sections whereby to predetermine the positioniof the housing. The stops l6 surround the 'housingand to some extent assist in preventing the escape of air from the conduit,

' particularly when a back pressure develops. Ob-

spond with the cross-section of the conduit or flue 9. The housing includes, among other things, parallel side walls I! and I8, and top and bottom walls l9 and 20, respectively.

An auxiliary casing or hood part generally designated 2| is preferably provided adjacent the upper extremity of the side wall I! of the housing H, with its longitudinal axis disposed in spaced apart parallel relation to the longitudinal axis of the housing. This casing or hood 2| is of a size sufficient to freely receive the damper retarding mechanism or dashpot l4, above referred to, The hood includes, among other things, a top wall portion 22 which is joined to a side wall portion 23 by a radial portion 24, and end wall DOD-T extremity thereof may be arranged at an angle with reference to its upper extremity, in orderto possibly better receive the air that is being forced through the conduit.

A bracket generally designated 43 is secured adjacent the upper end of the damper I3 by spot welding, or other desirable means, and includes a relatively large flat base portion 44 which engages the bottom wall of the damper in order to reenforce same to some extent. One extremity of the base portion 44' is provided with a lug 45 which extends outwardly substantially at right angles with reference to said base portion, and the other extremity of the base is provided with a lever or: arm 46 which extends outwardly in thesame general direction as the lug 45, and at top wall I!) of the housing, and the side wall 23 is disposed in spaced apart parallel relation to' the wall ll, the latter being common to both the housing and hood. The hood may be open at its lower extremity, as shown, andtheend walls 25 and 26 preferably terminate short of the ends of the housing.

The upper extremity of the hood adjacent one end is preferably provided with an upwardly extending hollow enlargement or bulge 21, the arcuate or curved top wall of which is arranged approximately flush with the top wall 19 of the housing l2. The side wall I! of the housing also provides a sidewall for this enlargement, and the other side wall 29 of said enlargement is preferably provided with a more or less centrally disposed inwardly extending generally circular boss portion 30, and a laterally projecting portion 3| located at one side of the boss in parallel relation to the end walls 25 and 26 of the auxiliary casing or hood. The boss andprojection are preferably integrally connected to the arouate top wall 28 and also to each other by a connecting portion 32. These portions are so constructed that same are reenforced by each other and at the same time brace portions of the enlargement 21. The projection or depending portion 3| provides a stop whereby to limit movement of the damper in one direction'and will be discussed morein detail later. H

The boss 30 is preferably provided with a threaded hole 33, shown in Figures 2 and 7, which receivesa screw 34 having a conical bearing point 35 providing one of the bearings for the damper l3. 3

The upper extremity of the side wall 18 of'the housing is provided with .an outwardly extending generally cylindrical boss 36, somewhat similar to the boss 30, and has a threaded hole which receives a screw 31 having a conical point 38 whereby to provide the other bearing for the damper I3. These set screws 34 and 31 may each be provided with a slot so that the screws may be easily adjusted by a screw driver or other tool, and lock nuts 39 may be used to lock the screws in place after they have been adjusted. An aperture 40 is provided in the side wall I! of the housing in line with the threaded holes in the bosses 30 and 36. d

The damper I3 is preferably of channel shape and includes a "bottom wall 4| and relatively short side walls 42, and is of a size to substantially or completely close-the air passage formed by the housing l2, when'moved from its normal angular full line position to its lowermost dotted line position, as illustrated in Figure 3.

otherwise than illustrated, for examplethe lower an acute angle with reference to the base. This arm 46 is arranged in an offset relation with respect to the base portion 44 by means of an ex tension 41, which extension is a continuationof saidbase portion. The arm and'lug are arranged in spaced apart parallel relation to each other and to the side walls of the housing l2. That portion of the arm adjacent-the extension 'or continuation 410i the basefarid the lug 45 are each provided with a conical bearing seat 48 whereby to receive "the points of the set screws 34 and 31 above referred to. The free end of the lever 46 is provided with a hole 49.

Thus far it should be apparent that the'damper may be centered within the housing [2 by means of the set screws 34 and 31, and that the extension 41 projects through the aperture 40 in the wall 11 and into the hood and enlargement 27, and is in connection with the means 14 for re tarding movement of the damper. Itwill also be apparent that the depending lever arm 46 when moved to a predetermined position to the left by the pressure of the air against the damper will engage the stop 3| for the purpose of' limiting the movement of the damper in one di rection.

The device for retarding movement of the damper is preferably of 'a size to fit substantially entirely within theconfin'es of thehood 2| and, includes among 'other'things, a tubular cylindrical' metal member 50, closed at one end by a plug 5| permanently secured in place by a pressed fit or otherwise whereby to completely seal said end. This plug has a cylindrical portion'52 and a flange 53 which tightly engage the inner wall and the end wall of-said tubular member, respectively. The member 50 and plug 5| are'preferably made of die cast material.

One side of the portion 52 ispreferably provided with an axially extending spindle 54 which projects through a generally rectangular hole 55 provided in the end wall 25 of the hood. This spindle is made cylindrical as indicated at 56 near-the portion 52, and the remainder is preferably flattened on opposite sides, the unflattened portions being threaded whereby to engage a'knurled nut 51. One side of the nut is adapted to cooperate witha scale 53, provided on the'flattened inclined side open to view. This arrangement prevents rotation of the member 59 and'spindle 54, and provides means for adjusting the angle of the damper to suit various conditions. More specifically, the nut may be rotated so that one face thereof will register with numeral 2 on the scale, in which event the damper would nearly close the air passage, and very little air pressure would be required to pivot the damper. If the nut were rotated to register with numeral 5. the damper wouldbe'elevated.

and a greater pressure would be required to operate it. 'In order to prevent tilting ofthe element when the device is operating, the end wall 25 of the hood'is' preferably provided with an inwardly extending boss 59 through which the spindle'54 extends. g

The other side of the portion '52 of the plug 51 is provided with an axially extending centrally disposed tubular protuberance 69, within which one extremity of a" resilient element, in the form of a tightly coiled spring BI is permanently secured by depressing portions'of the protuberance against the spring. The other end of the spring is similarly permanently secured within a central round tubular protuberance 62 provided on a connecting piston member or link generally designated 63. This piston is preferably made of die cast material, and includes the protuberance 62 just referred to; an annular portion 64 having a concave groove or cove 65 in its periphery; and an axially extending round spindle 66 which is preferably bifurcated at its free extremity to receive the free end of the arm 46 secured to the damper 13. A cotter pin 61 or other desirable means extends through holes provided therefor in the spindle 66, and through the hole 49 in the lever arm 46 whereby to pivotally connect the element 63 with respect to the arm, as most clearly shown in Figure 3.

When air under pressure is forced through the housing l2 in the direction indicated by the arrow in Figure 3, the damper will move downwardly to some extent as indicated by the dotted lines, expanding or stretching the spring 6 I and when the air pressure diminishes or the blower is shut on, a resilient cylindrical piston ring 68 functions to ease the return movement of the damper back to its elevated full line position. The piston ring 68 is preferably constructed from soft rubber or the equivalent in the form of a generally tapered cylinder, the larger extremity of which is preferably slightly flared or belled while the opposite extremity is provided with an internal annular convex bead portion 69 which snugly fits within the cove or groove 65 f the piston 63. The outer surface of the belled larger extremity of the cylindrical ring is adapted to frictionally engage the inner wall of the element 50, and when the air pressure in the system diminishes the piston is moved inwardly due to the action of the spring 6| causing the compressed air within the chamber formed by the member 50, to be expelled through a port "H1 provided in the wall of the member 50. Accordingly, it is apparent that the dashpot acts as a check, and that the spring and ring function to counteract each other during the swinging movements of the damper.

Having thus described my invention, it is obvious that various modifications may be made in the same without departing from the spirit of the invention; and, therefore, I do not wish to be understood as limiting myself to the exact form, construction, arrangement, and combination of parts herein shown and described.

I claim:

1. A tubular housing adapted to form part of a fluid conduit, a damper movably disposed in said housing, elongated stationary means provided on said housing including a side wall and an end wall, bracket means pivotally connecting said damper to one of the walls of said housing and to said side wall, means connected to said bracket for progressively retarding movement of said damper, and an adjustable connection connectin said last-mentioned means to said end wall.

2. In combination: a fluid conduit, a housing interposed 'inlsaid conduit and forming a-part thereof, a wall integralwith and arranged in spaced relation to awall of the housing, a damper disposed in said housingfa bracket for supporting said damper having abearing on one of the walls of the housing, an extension of said bracket projecting "through another wall of the housing and having a bearing on said integral wall, a lever carried'by said bracket, and means for progressively retardingmovement of the damper having a part connected to said lever and a part to a portion of said integral wall. 9 3. Means-for'assisting in the control of the flow of afiuid through a conduit including, a housing, a wallintegral with and disposed in spaced apart relation to a first wall of the housing, a second wall arranged transverse to said integral wall and to said first wall of said housing, a damper disposed in said housing, a bracket supporting said damper having a bearing on said first wall, said housing having another wall between said integral wall and said first wall, an aperture provided in said another wall, said bracket being provided with an extension projecting through said aperture and having a bearing on said integral wall, a lever carried by said bracket, and a dashpot having a part connected to said lever and a part to said second wall forprogressively retarding movement of the damper.

4. Means for assisting in the control of the flow of a fluid through a conduit including, a housing having a first wall, a wall integral with and disposed in spaced apart relation to said first wall, a second wall arranged transverse to said integral wall and to said first wall of said housing, a damper disposed in said housing, a bracket for supporting said damper having a bearing on said first wall, said-housing having another wall provided with an aperture, said bracket being provided with an extension projecting through said aperture and having a bearing on said integral wall, a lever carried by said bracket, a dashpot having a part connected to said lever for progressively retarding movement of the damper, and a part to said second wall, and abutment means provided on said integral wall for limiting movement of the damper in one direction.

5. In an air control device, a housin unit including first, second, and third walls arranged in.

generally spaced apart parallel relation, a damper disposed between said first and said second walls, an aperture provided in said second wall, a bracket supporting said damper projecting through said aperture and having bearing on said first and third walls, connection means carried by said bracket, and means for progressively retarding movement of the damper havin a part connected to said connection means and a part connected to the housing.

6. In an air control device, a housing unit generally rectangular in cross-section including a pair of substantially parallel walls, a damper disposed between said walls, a supplemental wall arranged in spaced apart parallel relation to said pair of walls, an aperture provided in one of said pair of walls, a bracket supporting said damper having a bearing on said supplemental wall and projecting through said aperture and having a bearing on the other of said pair of walls, means arranged between said other wall and said supplemental wall and connected to the bracket for progressively retarding movement of the damper, and means providing an adjustable connection between said retarding means and a part of the housing.

7. In an apparatus of the character described, a

tubular housing, a .hood providedadjacent .one side of the housing; a damper 'movably mounted in said housing, dashpot-means for retarding the movement of the damper arranged in the hood alongside said housing and operatively connected to'said damper, said 'clashpot meansincluding a cylinder, piston means movable in the cylinder, rigid means projecting from the piston means and rigidly connected thereto and'means connecting the rigid means to the damper so that on movement of the damper the rigid'means will be caused to move in a path at an angle to the axis of the cylinder,said piston means being 50 constructed and arranged that at least a portion thereof may tilt relative to said-rigid means while maintaining contact with the-walls of the cylinder,

8. In an air' control device, a housin-g unit including first, secondpand third walls arranged in generally spaced apart parallel relation, a damper disposed between said first and said second walls, an aperture provided in said second wall, a bracket supporting said damper projecting through said aperture and having bearing on said first and third walls, connection means carried by said bracket, and dashpot means for progressively retarding movement of the damper having a part connected to said connection means and a part connected to the housing.

BERNARD M. GUTHRIE. 

